OK, so I know that a second portal is in progress. So, I had an idea for a package from valve entirely made of portal games( note that two of them I made up, they are not confirmed, I just thought these would be cool additions). These are my ideas for what would be in the package.

Portal: the first one of the series

Portal 2: the sequel to Portal, the core single player experience of the package ( maybe it could have the gravity gun in it as well for added depth to the puzzles?)

Portal- Companions: A completely different adventure from portal 1 and 2 where you team up with someone online and tackle puzzles that are meant to be solved with two people wielding one portal gun each.

Portal- Races: a multiplayer only experience where players are pitted against each other on a variety of maps and use portals to get at the end of the map as fast as they can. You start out at a starting line (similar to a racing game) and you use portals to get past the particular obstacles in the level. you cannot use anyone elses portal but your own. Some obstacles would be deadly if you dont complete them the right way (a pit of spikes or lava would be a cool example) and then you would start at the beginning of the level, with your portals all in place (so that there is still a chance people could catch up after dying). First one to the finish wins.